Vascular dementia (VD) is a term that broadly refers to issues with reasoning, planning, judgment, memory, and other thought processes that are brought on by brain damage from decreased blood supply to the brain. Vascular dementia is not always caused by strokes; however, it can occur after a stroke affects an artery in the brain. There is no standardized treatment for vascular dementia. Based on the symptoms that are present, pharmacological agents are advised if required. According to the literature drugs used in hypertension can be used for vascular dementia.
Will hypertension cause VD?
Hypertension is one of the most common conditions evident in around 30-45 % of the general population and has been linked to dementia and cognitive decline. Recent studies have indicated that hypertensive patients had a 30% higher risk of developing dementia than the general population. Uncontrolled high blood pressure can harm the blood vessels, weaken the vessel wall, and increases the risk of rupture or blockage. This limits the blood flow to specific areas of the brain, preventing enough oxygen and nutrients from reaching the brain cells and causing damage. High blood pressure can reduce the flow of blood to the brain and result in vascular dementia in three primary ways:
Damage to the blood vessels in the brain: This can cause blood vessels to narrow and stiffen. This condition is referred to as small vessel disease. This is the most frequent reason for vascular dementia.
Stroke: A stroke occurs when a blood vessel in the brain becomes narrow or bursts. It prevents the blood flow to a portion of the brain, resulting in damage. The term for this is post-stroke dementia.
Transient ischemic attack (TIA): commonly referred to as a small stroke. This can gradually worsen the condition if repeated. Multi-infarct dementia is the term used for it.
What is amlodipine and how it acts?
Amlodipine is a calcium channel blocker available under the trade name Norvasc®. Given orally, the side effects of this drug include swelling, exhaustion, abdominal pain, and nausea.
The "calcium theory of dementia" may provide the most logical justification for amlodipine's benefits in vascular dementia.
According to this theory, levels of calcium at pre and postsynaptic terminals get altered with age which is responsible for dementia and cognitive changes in the brain.
These levels are mediated by voltage-gated calcium channels through the release of a neurotransmitter called glutamate.
Amlodipine which belongs to the calcium channel blocker group of drugs works by blocking all types of calcium channels that are present at the synaptic terminals and reduces the activity of calcium which is responsible for all these neurodegenerative changes.
When to use amlodipine in VD?
It has been established that amlodipine can also be used for the treatment of hypertension, and coronary artery disease. These two diseases are considered potential risk factors for VD. When they are identified earlier and amlodipine is advised as a treatment regime, the chances of getting vascular dementia can be minimized to a greater extent.
Vascular dementia can also occur due to other risk factors such as diabetes, excessive accumulation of cholesterol, and triglycerides, sedentary lifestyle, smoking, and alcohol consumption. In these conditions also amlodipine can be given to reduce vascular dementia and cognitive abilities that are associated with VD. It acts by controlling the influx of calcium, which is responsible for these neurodegenerative changes. Apart from amlodipine, other calcium channel blockers like nifedipine, felodipine, and nicardipine can also be used for this purpose. But they have been proven to have a lesser effect on dementia and cognitive changes compared to amlodipine. The reason could be attributed to their inability in blocking all types of calcium channels present at nerve terminals, which indirectly control the amount of calcium circulating at the synaptic terminals.
Hope is the last thing that is ever lost
There are currently no established clinical treatments for vascular dementia, and the exact mechanism through which it arises has remained a mystery. Amlodipine if used properly may reduce dementia to some extent. As symptoms of VD are appearing in patients sooner than ever before, more research is required to give hope to the patients that the progression of this deadly disease can be reduced.
A. D. Korczyn, V. Vakhapova, and L. T. Grinberg, “Vascular dementia,” J Neurol Sci, vol. 322, no. 1–2, pp. 2–10, Nov. 2012, doi: 10.1016/j.jns.2012.03.027.
C. A. Emdin et al., “Blood pressure and risk of vascular dementia: evidence from 4.3 million adults and a cohort study of TIA and stroke,” Stroke, vol. 47, no. 6, pp. 1429–1435, Jun. 2016, doi: 10.1161/STROKEAHA.116.012658.
L. Feldman et al., “Amlodipine treatment of hypertension associates with a decreased dementia risk,” Clin Exp Hypertens, vol. 38, no. 6, pp. 545–549, 2016, doi: 10.3109/10641963.2016.1174249.
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